Mining machine



1927' H. c. JOHANSEN MINING MACHINE :s Sheets-Sheet l Filed May 12, 1919 1927' H. c. JOHANSEN MINING MACHINE 3 Sheqts-Sheet 2 3 Sheets-Sheet 3 H. C. JOHANSEN MJENING MACHINE Filed May 12, 1919 Oct. 11, 1927.

Patented a. 11,1927.

ma! 0. 30mm,

WY OOBfANY,

PATENT OFFICE.

01 IIOEIGAN cm, INDIANA, ASBIGH'OB '10 SULLIVAN HA- A CORPORATION 01 MASSACHUSETTS.

HINDIG IAOHIHE.

Application filed lay 18, 1919, Serial 1C0. 986,688. Benew'ed January 8, 1,027.

This invention relates to mining machines and especially to a means for driving entries or tunnels.

One object of the present invention is to provide an improved mining machine. Another object of the present invention is to rovide an improve mining machine for driving entries or tunnels and one of such a character that the machine roduces a l finished tunnel during a tunne mg operation, it being unnecessary to use 0t er tools or means for removing projections or leveling the floor. Still another object of the present invention is to provide an improved l self-centering tunnelin devise which is automatically guided uring a tunneling operation and which may be continuously operated to cut a tunnel head. Still another ject of the present invention is to rovide an improved tunneling device whic operates on a tunnel head to drive the latter forward and which removes the cuttings to a point remote from the tunnel head and loads the cuttings onto a car. These and other objects and advantages of my improved construction will, however, hereinafter more fully appear.

In the accompanying drawin s I have shown for pur oses of illustration several an embodiments w ich my invention may assume in practice.

In these drawings,-- Fig. 1 is a side elevation of my improved mining machine in operative position in a 85 tunne Fig. 2 is a plan view thereof. Fig. 3 is an end view of my improved mining apparatus.

Fig. 4 is a detail side elevation of a modified form of driving mechanism.

Fig. 5 is an end elevation thereof. In the illustrative embodiment of my invention I have shown a truck 1 mounted on a lurality of axles 2 and 3 adapted to carry w eel elements on which the truck moves The forward axle 2 referably carries sup porting caterpillar w eels 4 through which the truck is driven in order that the heaviest part of the machine, which in this embodi- 6 ment of the invention is mounted on the forward end of the truck, will be provided with a broad supporting means which will not break in the mine floor and in order that the more heavily weighted and may be availed of for securing proper traction on the mine floor. If desired, other types of wheels may be mounted on the rear axle 3, but because the weight on the rear end of the truck is relatively small, I herein preferably rovide wide rimmed wheels 5 thereon. he axle boxes 6 carried on the ends of the axles 3 are preferably adjustable in gllbs 7 herein shown formed integrally with t e truck, the axle boxes 6 being vertically adjustable in the gibs upon an adjustment of an elevating screw 8 for'adjusting the height of the rear end of the truck and thereby the inclination of the cutting mechanism to the axis of the tunnel or the tunnel head.

If desired, various forms of cutting mechanism may be mounted u on the truck, but I preferably provide a p urality of cutting mechanisms which simultaneously cut a plurality of intersecting passa es or chambers, herein in the form of two ores uniting to form a mine entry which may easily be made into one in such a manner as to provide at once a suitable bottom or roadway on which the tunneling machine may be 0 erated and on which trackways may be aid. In the preferred embodiment of my invention these cutting mechanisms comprise two cutter heads or arms 9, 10 rotatably mounted on shafts 11, 12 mounted in suitable bearings 13, 14 on the truck 1 in such a manner that the heads 9, 10 project in front of the truck, and the heads are set preferably at an angle to each other so that they may be simultaneously operated to cut intersecting or overlapping bores. The front ends of these cutter heads are preferably formed V-shaped or convex and the cutting bits 15 are preferably formed in two or more, herein parallel, series on the edges of the V-shaped section of the cutter head so that the transverse thrust of the bits will be equalized and no other means will be required to keep the head pro erly centered in the tunnel. The bits use are preferably removable for sharpening and are held in position by suitable means such as set screws 16. The pro er clearance for the cuttingheads is provided by the use of reaming bits 17 mounted on the sides of the cutter heads.

The cutter heads just described properly center the front end of the truck in the intersectin bores which are cut by this cutting mec anism, and to retain the rear end of the truck in proper alignment with the tunnel, I rovide a iding means mounted adjacent t is rear en this guiding means in the form shown being mounted on each side of the truck on standards 18. Projecting laterally from these standards are brackets 19 carryin guiding wheels 20 which may be adjusted aterally in the brackets as by means of bolts 21 in which the wheels are rotatabl mounted, and adjusting nuts 22 threads thereon. The adjusting nuts are manipulated by means of a dpinch bar which may be inserted in a ra ial opening 23 formed in the adjusting nut, althou h as is obvious, other ad usting means may e used. By this improved ad'usting means and also by the means above escribed for adjusting the elevation of the rear end of the truck,

the position of the cutting mechanism rela-- tive to the axis of the tunnel may be varied so that a straight or a curved tunnel will be driven.

If desired, a plurality of actuating means may-be used, but in the preferred form of my invention I preferably use a single motor 24 mounted adjacent the rear end of the truck, the cutter heads being driven from this motor by means of a motor shaft 25, beveled gears 26, jack shaft 27, spur gears 28, and a second jack shaft 29 which drlves the shafts 11 and 12 by means of worms 30 fixed to the second jack shaft 29, and worm gears 31 fixed to the cutter head shafts 11 and 12. This drive provides a simple and powerful connection between the motor and the driving shafts 11 and 12 through a triple reduction gearing, that is, the gears 26, 28 and the worm drive 30.

While the mechanism for driving the truck may be taken from the truck shaft 25 or the jack shafts 27 and 29, I preferably drive the motor driving mechanism from the extended end of one of the driving cutter head shafts, as shaft 11, for the truck must necessarily move very slowly and the use of a. second speed reducing means would lower the efiiciency of the apparatus and increase its weight and the number of the wearing parts. The truck driving mechanism preferably has a reversing mechanism mounted in a gear box 32 in which oppositely driving gears 33 and 34 may be connected as by means of a clutch 35, controlled by lever 36, which may be thrown to drive a shaft 38 in either direction and thus impart a rotary movement to a driving, shaft 39 through a chain 40 passed over suitable sprocket wheels mounted on the shafts 38 and 39. This last named shaft carries adjacent one end thereof a worm 41 which drives the axle 2 through a worm gear 42, the axle 2 in turn pauper imparting its rotating motion to the caterp 1l ar wheels by means ot a r 43 which intermeshes with the caterpi lar treads in a well known manner. By this improved mechanism, it is seen that a single motor is used to operate the cutting mechanism and to advance or retract the tunneling machine in a tunnel and that the proper speed reduction for the cutting mechanism and for the truck drive is produced with a very small number of moving parts.

As these two intersecting tunnels are driven forward it is seen that each comprises a substantially circular bore and that these tunnels are partially separated by V-shaped walls which project from the roof and floor of the tunnel. To form one tunnel of the intersecting bores, to provide a proper bottom or floor for the single tunnel. and to remove the obstructing wall which would pro ect inwardly from the roof of this tunnel, I provide two cutter bars 44 and 45. the first of which removes the intervening wall at the bottom of the tunnel and prepares a level floor, and the latter of which removes the depending wall from the roof of the mine. In the preferred form of my invention, each of these cutter bars com prises a rotating member having a plurality of spiral ribs 46 carrying cutter bits 47 herein shown as similar to the cutter bits 15. Thedower cutter bar 44 is mounted in the bearings 48 which project downwardly from the truck, and is driven preferably by a chain 49 which asses over suitable sprocket wheels on the ack shaft 29 and the shaft 50 of the cutter bar 44. The upper cutter bar 45 is mounted in suitable bearings 51 carried by standards 52 mounted on the truck, the cutter bar being driven in the proper direction by a chain 53 which passes over a second sprocket wheel carried by the jack shaft 29, and a sprocket wheel mounted on a stud shaft 54 carried by one of the vertical standards, this latter rocket having a drivmg connection with t e shaft of the cutter bar 45 through a pair of reverse gears 55.

The material which is cut from the tunnel head is preferably removed so that an accumulation of cuttings will not change the depth of the tunnel and impede the forward movement of the cutting mechanism as the tunnel is advanced. For th s purpose, I provide, in the improved form of mv invention. a plurality of scoops or shovels 56 herein shown as formed in the cutter heads 9 and 10 in such a manner that as the cutter head revolves, these scoops will pick up the cuttings from the bottom. As the arms of the head approach their upper vertical position, the material picked up by these scoops will be transferred therefrom by chutes 57 to a ward more rapidly.

passes over a driving roller 60, driven from the jack shaft 29 as b a chain 61, the belt being carried rearwar ly over suitable rollers 62, 63, and 64 mounted on elevated support 65 so that the material removed by the cutting mechanism may be deposited at the rear of the tunneling machine in small mine cars which ma be run under the rearwarclly projecting en of the support 65 for th s purpose. This hopper 58 18 preferably extended laterally from the belt conveyor 59 so that it receives the cuttings from the pluralit of chutes carried by the two cutting hea s 9 and 10 with the result that but a single conveyor 59 is required to remove the cuttings from the two cutting mechanisms which drive the two intersecting bores. As is obvious, other well known conveying means may be used in place of the belt conveyor shown.

If it is desired to move the mining machine forward intermittently instead of at a constant velocity, the driving means shown in Figs. 4 and 5 may be substituted for the continuous driving means above described.

In this modified form of my invention, a driving disc 66 may be mounted on one end of the shaft 12 and this disc may be attached to a driving link 67 as by an adjustable connection as shown at 68, this connection being such that when this end of the link is moved outward between the gibs 69'carried by the disc, the throw of the link will be greater and the machine will be driven for- Attached to the other end of this link 67 is a rotating support 70 pivotally mounted as shown on a shaft 71 carried by a bracket 72 rigidly secured to the truck frame. Mounted also on this shaft 71 is a ratchet wheel 73 securely fastened to the truck drive shaft 71, this ratchet wheel being driven by a pin 74 having a beveled edge on the inner end thereof by means of which the pin may be moved about the axis 71 in one direction independent of the ratchet wheel 73 but the pin 74 when rotated in the opposite direction will catch the ratchet teeth and rotate the shaft 71. If desired, the truck may be driven in various ways but I preferably provide another speed reducing means between the truck driving means and the driven wheel, this speed reducing means being illustrated in Figs. 4 and 5 as a pinion 78 mounted on a jack shaft 77, the latter being driven by the shaft 71 by a. inion drive and the worm 78 in turn driving the axle 2 through a spur gear 79. A pawl 75 pivotally mounted on a suitable bracket 76 and held in operative position against the ratchet wheel 7 3 by means of a spring is also provided to prevent a backward movement of the ratchet wheel. As is clearly shown in Fi 5 if the positions of the pin 74 and pawl 5 be reversed, the ratchet wheel will be driven in a reverse direction and the mining machine will be backed away) from the tunnel head. Further 11'. will e seen that the driving mechanism may be adjusted to drive the cutting mechanism forward at varying speeds according to the quality of the material being cut, adjusting the link end 68 between the g1 s 69 so as to get a greater or smaller throw of the link 67.

From the foregoing, it will be clear that when 1t is desired to drive a tunnel or entry, the mmmgmachine above described may be used for this purpose and that this machine will drive the tunnel, prepare the bottom for the reception of ties or to serve as a road bed, Wlll remove all obstructions in the tunnel, and that the tunnel may be driven straight forward, curved to right or left or driven at different grades. It will further be noted that if only a small tunnel is desired, one of the heading machines alone may be used, and that the lower cutter bar may be used to flatten out the lower section of the tunnel to serve as a roadway. When using my improved mining machine in the preferred form as shown in Figs. 1, 2, 3, it will be seen that the cuttings made at the heading will be automatically elevated by the cutter bars, dropped into a suitable hopper, and carried to the rear of the machine where this material may be dumped into dump cars such as are commonly used in mines, thus removing at once all the dbris from the tunnel head and keeping the cutting tools working to their maximum efiiciency.

While I have in this application specifically described several embodiments which my mventlon may assume in practice, it is to be understood that these forms are used for illustrative purposes only and that the inventlon may be modified and embodied in various other forms without departing from its s irit or the scope of the appended claims.

hat I claim as new and desire to secure by Letters Patent is:

1. In a tunneling device, a plurality of cutting mechanisms adapted to cut parallel entries, and supplemental cutting mechanism for joining said entries.

2. In a tunneling device, a plurality of cutting mechanisms adapted to cut intersectmg entry passages, and means for removing a wall partially separating said passages.

3. In a tunneling device, a plurality of cutting mechanisms adapted to cut intersecting entry bores uniting to form a mine entry, and supplemental cutting mechanism fog joining said bores to form a single tunne 4. In a tunneling device, a plurality of cutting mechanisms adapted to cut intersect ing entry bores uniting to form a mine entry, and a cutting mechanism for removing irregularities left by said first named cutting mechanisms.

5. In a tunneling device, a plurality of cutting mechanisms, means for simultaneously operating said mechanisms to cut a plurality of intersecting entry bores uniting to form a mine entry, and means for removing a wall partially se arating said bores.

6. In a tunneling evice, a plurality of entry passage cutting mechanisms, means for operating said mechanisms in intersecting curves to form a mine entry, and means for removing a wall partially separating said passages.

7. In a tunneling device, a plurality of axes, entry passage cutting mechanisms mounted thereon and comprising cutting heads cooperating to form a mine entr the cross sectional dimension of said hea s being greater than the distance between the axes at the points of connection between the heads and axes, and means for removing a wall partially separating said passages.

8. In a tunneling device. a plurality of parallel axes, passa e cutting mechanisms rotatively mounted tliereon and comprising a plurality of transversely disposed cutting arms whose length is greater than the distance between the axes, and means for removing a wall partially separating said passages.

9. In a tunneling device, a plurality of entry cutting mechanisms, means for operating said mechanism to cut a plurality of longitudinally disposed entry chambers forming a mine entry, means for removing a wall separating said chambers, and a single means for connecting said cutting mechanisms and wall removing means.

10. In a tunneling device, a plurality of entry cutting mechanisms, means for operating said mechanisms to cut a pluralit of longitudinally disposed entry cham ers forming a mine entry, and means comprising a transversely disposed cutting mechanism disposed between said cutting mechanisms for removing a wall separating said chambers.

11. In a tunneling device, a plurality of entry cutting mechanisms, means for simultaneously operating said mechanisms to cut a plurality of intersecting entry chambers forming a mine entry, and means comprising a, plurality of transversely disposed cutting mechanisms for removing walls partially separating said chambers.

12. In a tunneling device, a plurality of entry cutting mechanisms, means for simultaneously operating said mechanisms to cut a. plurality of intersecting entry bores forming a mine entry, means for removing a wall partially separating said bores, and a single means for actuating said cutting mechanisms and wall removing means.

13. In a tunneling device, a plurality of entry cutting mechanisms, means for simultaneously operating said mechanisms to cut a plurality of intersecting entry bores forming a mine entry, and means comprising a transversely disposed cutting mechanism for removing a wall partially separating said bores.

14. In a tunneling device, a plurality of entry cutting mechanisms, means for simultaneousl operating said mechanisms to cut a plurality of intersecting entry bores forming a mine entry, and means com rising a plurality of transversely dispose cutting mechanisms for removing walls partially separating said bores.

15. In a tunneling device, an entry cutting mechanism for removing the face and forming a mine entry, and a cutting mechanism for removing irregularities in a surface of the entry left by said first named mechanism.

16. In an entry driving device, a lurality of entry cutting mechanisms rotata le in an upright plane for removing the face and forming a mine entry, and cooperating cutting mechanism movable in a single plane for removing the bottom section of the entry to form a roadwa substantially between the axes of said cuttin mechanisms.

17 In an entry riving device, entry cutting mechanism rotatable in an upright plane for removing the face and formin a mine entry, and cooperating cutting mec anism for removing a top and bottom section of the entry.

18. In an entry driver, entry cutting mechanism comprisin a plurality of heads rotating in an uprig t plane to form intersecting bores forming a mine entry, and cooperating cutting mechanism for removing the bottom section of the entry to form a roadway.

19. In an entry driver, entry cutting mechanism comprising a pluralit of heads rotating in an upright plane to orxn intersecting bores forming a mine entry, and cooperating cutting mechanism for removing a top and bottom section of the entry.

20. In an apparatus of the class described, a plurality of rotary cutting mechanisms movable transversely of an entry to cut substantially the entire face thereof, a receiver, means carried by and rotatable with each of said mechanisms for elevating the cuttings and depositing them in said receiver, and a single conveying means for moving said cuttings from said receiver.

21. In a tunneling device, a truck, a plurality of rotating heads mounted to cut in intersecting paths adjacent one end of the truck, cutting mechanism carried by said heads, elevating means carried by said heads, and means for conveying cuttings from said elevating means to the opposite end of said truck.

22. In a tunneling device, a truck, a plurality of cutting heads mounted adjacent one end of said truck, and'rotatable about axes angularly disposed to the transverse face of the tunnel being cut, a hopper, automatically operative elevating means for periodically delivering the cuttings made by said cutting heads to said hopper, and a single means for delivering the cuttings to a point adjacent the opposite end of the truck.

23. In a tunneling device, a truck, a plurality of cutting heads mounted adjacent one end of said truck, a ho per, elevating means carried by said heads or delivering the cuttings made by said cutting heads to said hopper, and a single means for delivering the cuttings to a point adjacent the opposite end of the truck.

24. In a tunneling device, a truck, a plurality of cutting heads mounted adjacent one end of said truck, a hopper, elevating means carried by said heads for delivering the cuttings made by said cutting heads to said hopper, and an endless conve or for delivering the cuttings to a point a jacent the opposite end of the truck.

25. In a tunneling mechanism, a plurality of rotary cutter mechanisms, shoveling and discharging means on each of the same, and a hopper receiving the discharge from said shoveling and discharging means.

26. In a tunneling mechanism, a plurality of rotary cutter mechanisms, shoveling and discharging means on each of the same, a hopper receiving the discharge from said shoveling and discharging means, and a conveyor supplied from said hopper.

27. In a tunneling mechanism, a plurality of rotary cutter heads, cuttings collecting and discharging means on each of the same, said latter means being adapted to collect cuttings from a point outside of said heads, and means receiving the discharge from said means and delivering the same to a common point.

28. In combination, a truck, rotatable tunnel driving mechanism on one end thereof, and means for actuating" said mechanism and truck including a motor, aplurality of parallel shafts driving said mechanism and whose axes are angularly disposed to the axis about which said mechanism rotates, and a second set of parallel shafts successively driven by said other shafts and adapted to drive said truck and whose axes are parallel to the axis of rotation of said mechanism.

29. In combination, a truck, a plurality of cutting mechanisms carried thereby and rotatable on parallel axes, and driving mechanism therefor comprising a shaft transverse to the axes of rotation of said mechanisms, worm gear connections between each of said mechanisms and said shaft, a motor having its axis angnlarly disposed to the axis of said shaft. a second shaft operatively connected to said motor and said first mentioned shaft, and conve ing mechanism for receiving the materia removed by the cutting mechanism.

30. In combination, a truck, cutting mechanism carried thereby means for actuatin the same, and means for driving said truc includin a motor having its axis disposed longitudinally of said truck and fixed at all times against lon 'tudinal movement relative to the truck, a s aft parallel to said motor axis, a second shaft also substantially parallel to themotor axis and in spaced parallel relation to said first shaft, 9. driving axle, and driving connections between said motor and first mentioned shaft, said shafts, and said second mentioned shaft and axle.

31. In combination, a truck, cutting mechanism carried thereby, means for actuatin the same, and means for driving said trucE including a motor having its axis di d longitudinally of said truck and fixed at all times a ainst longitudinal movement relative to t e truck, a shaft parallel to said motor axis, a second shaft also substantially parallel to the motor axis and in spaced par allel relation to said first shaft, a driving axle, driving connections between said motor and first mentioned shaft, said shafts, and said second mentioned shaft and axle, said driving connections including a reversible gear mechanism 0 eratively connected to said first mentioned shaft.

32. In combination, a truck, tunnel driving mechanism on one end thereof, trucksupporting means at opposite ends of said truck including caterpillar tread mechanism beneath the end of said truck carrying said tunnel driving mechanism, means whereby said caterpillar treads may travel upon a substantially flat surface, and power means on said truck for driving said tunnel driving mechanism and said caterpillar tread mechanlsm.

33. In combination, a truck, tunnel driving mechanism on one end thereof, truck supporting mechanism including caterpillar tread mechanism beneath and on opposite sides of the end of said truck carrying said tunnel driving mechanism and truck supporting means beneath the opposite end of said truck, means whereby said caterpillar treads are allowed to travel upon a substantially flat surface, and power means on said truck for driving said tunnel driving mechanism and said caterpillar tread mechanism.

34. In combination, a truck, tunnel driv ing mechanism on one end thereof, truck supporting and driving mechanism includ ing caterpillar tread mechanism beneath the end of said truck carrying said tunnel driving mechanism and truck supporting means beneath the opposite end of said truck, power means on said truck for driving said tunnel and truck driving mechanism, and means between said truck and said truck supporting means for varying the elevation of said tunnel driving mechanism.

35. In a tunneling mechanism, aplurality of self-centering cutters mounted onshafts for rotation in an upright plane in intersecting paths, a support carrying said shafts and located in rear of said cutters, means for feeding said support longitudinally relative to the bottom, and guidingwmeans by and movable with said mechanism adjustable laterally to maintain the rear end of said support in alinement with the tunnel during simultaneous movement of said cutting mechanism and support.

36. In a tunneling mechanism, a plurality of cooperating self-centering cutters rotatable in an upright plane in intersecting paths, :1. support carrying said cutters an located in rear thereof, means for feeding said support longitudinally relative to the bottom, and means carried by and movable with said mechanism for varying the elevation of the rear end of said support.

37. In a tunneling mechanism, a truck, tunnel driving mechanism thereon, a motor, reduction mechanism between said motor and said tunnel driving mechanism, and tunnel shaping mechanism driven by said reduction mechanism and including cooperating cutters operating to shape the top and bottom of the tunnel. g

38. In a tunnel mechanism, a truck, tunnel driving heads thereon, a motor, reduc tion mechanism between said motor and said tunnel driving heads, and tunnel shaping mechanism driven by said, reduction mechanism and including a roadway forming cutter operating between said heads.

39. In a tunneling mechanism, a truck, tunnel driving mechanism thereon, a motor, reduction mechanism between said tunnel driving mechanism and motor, and tunnel shaping mechanism driven by said reduction mechanism and including cooperating oppositely rotating cutters operating to shape the top and bottom of the tunnel.

40. In an entry driving mechanism, a support movable lon 'tudinally of an entry, a plurality of hea s rotating in an upright plane in intersecting paths, cutters on said eads operating the bottom ad acent the face, and cuttin 3 handling mechanism includin cuttings co lecting means carried on saidaieads and deliverin to a central point.

41. n an entry driving mechanism, a support movable lon itudinally of the ant plurality of hea s rotating in an upright plane in intersecting paths, cutters on said heads operating to deliver the cuttings on the bottom adjacent the face, and cuttin s handling mechanism including cuttings co lecting scoops carried on said heads and havin communicating cuttingsguiding surfaces de ivering to a central point.

In testimony whereof I allix my signature.

HARRY G. J OHANSEN.

CERTIFICATE or CORRECTION.

.50 to deliver. the cuttings on ing means for varying the elevation of said tunnel driving mechanism. a

35. In a tunneling mechanism, a plurality of self-centering cutters mounted on shafts for rotation in an upright plane in intersecting paths, a support carrying said shafts and located in rear of said cutters, means for feeding said support longitudinally relative to the bottom, and guidingmeans by and movable with said mechanism adjustable laterally to maintain the rear end of said support in alinement with the tunnel during simultaneous movement of said cutting mechanism and support.

36. In a tunneling mechanism, a plurality of cooperating self-centering cutters rotatable in an upright plane in intersecting paths, a support carrying said cutters an located in rear thereof, means for feeding said support longitudinally relative to the bottom, and means carried by and movable with said mechanism for varying the elevation of the rear end of said support.

37. In a tunneling mechanism, a truck, tunnel driving mechanism thereon, a motor, reduction mechanism between said motor and said tunnel driving mechanism, and tunnel shaping mechanism driven by said reduction mechanism and including cooperating cutters operating to shape the top and bottom of the tunnel.

38. In a tunnel mechanism, a truck, tunnel driving heads thereon, a motor, reduction mechanism between said motor and said tunnel driving heads, and tunnel shaping 85 mechanism driven by said reduction mechanism and including a roadway forming cutter operating between said heads.

39. In a tunneling mechanism, a truck, tunnel driving mechanism thereon, a motor, reduction mechanism between said tunnel driving mechanism and motor, and tunnel shaping mechanism driven by said reduction mechanism and including cooperating oppositely rotating cutters operating to shape the top and bottom of the tunnel.

40. In an entry driving mechanism, a support movable longitudinally of an entry, a plurality of heads rotating in an upright plane in intersecting paths, cutters on said eads operating to deliver the cuttings on the bottom adjacent the face, and cuttin s handling mechanism includin cuttings co lecting means carried on said%1eads and deliverin to a central point. 56

41. n an entry driving mechanism, a support movable lon itudinally of the entry, a plurality of hea s rotating in an upright plane in intersecting paths, cutters on said heads operating to deliver the cuttings on 60 the bottom adjacent the face, and cuttings handling mechanism including cuttings collecting scoops carried on said heads and havin communicating cuttingsguiding surfaces delivering to a central point.

In testimony whereof I afiix my signature.

HARRY C. JOHANSEN.

CERTIFICATE or CORRECTION.

Patent No. 1, 645,007.

Granted October 11, 1927, to

HARRY C. JOHANSEN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page I, line 15, for the word "devise" read "device" and line 45, after the word "moves" insert a period; page 2, line 44, for "truck" read "motor", and line 46, for "motor" read "truck"; page 5, line 1, claim 22, after the word "truck" strike out the comma; page 6, line 9, claim 35, after the word "means" insert the word "carried"; same page, line 23, claim 36, after the syllable "tion" insert the words "and lateral position"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day of November, A. D. 1927.

Seal.

M. J. Moore, Acting Commissioner of Patents.

CERTIFICATE or CORRECTION.

Patent No. 1,645,007. Granted October 11, 1927, to

HARRY C. JOHANSEN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 15, for the word "devise" read "device" and line 45, after the word "moves" insert a period; page 2, line 44, for "truck" read "motor", and line 46, for "motor" read "truck"; page 5, line 1, claim 22, after the word "truck" strike out the comma; page 6, line 9, claim 35, after the word "means" insert the word "carried"; same page, line 23, claim 36, after the syllable "tion" insert the words "and lateral position"; and that the said Letters Patent should be read with these corrections therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 1st day of November, A. D. 1927.

M. J. Moore,

Seal. Acting Commissioner of Patents. 

